Primary CV prevention with aspirin may be more harmful than beneficial in diabetics

Using aspirin for the primary prevention of cardiovascular (CV) diseases appears to confer increased harm and lack of survival benefit, yielding a modest decrease in major adverse CV events (MACEs) but a concomitant elevation in major bleeding, according to a study.

Researchers performed a systematic review of studies evaluating the impact of aspirin in patients with diabetes in primary prevention. The search yielded 466 published studies, of which 10 were included for analysis. Four of the studies were randomized controlled trials (RCTs) in diabetic patients exclusively, while six studies corresponded to subgroup analysis of RCTs.

The total population comprised 34,058 diabetic patients with a median age of 63.75 years, and 50.6 percent were men. The median follow-up was 5.73 years. Seven studies used a low daily dose of aspirin (75–100 mg), two studies used 100 mg and 325 mg on alternate days, and one used two tablets of 325 mg aspirin per day.

Pooled data revealed that aspirin did not improve all-cause mortality (risk ratio [RR], 0.96, 95 percent confidence interval [CI], 0.90–1.03; seven RCTs; n=27,595), although it lowered MACE risk by 8 percent (RR, 0.92, 95 percent CI, 0.84–0.999; I², 0 percent; eight RCTs; n=29,814).

More importantly, aspirin use contributed to increased risks of major bleeding (RR, 1.30, 95 percent CI, 1.10–1.53; two RCTs; n=18,019 patients) and major gastrointestinal bleeding (RR, 1.39, 95 percent CI, 1.08–1.80; two RCTs; n=18,019).

There were no significant differences observed in the risks of cardiovascular mortality, myocardial infarction, stroke, and amputation between the aspirin and control arms.